How can I move bunch of vertices to the origin of the world properly with Sverchok?
List Math average isn't what I would use to find the average vector, we have an analyzer node for that. It expects inputs of Vertices, and employs an appropriate algorithm for that kind of input.

List Math expects primarily lists of numbers, (signified by the type of socket : green ) tweaking the level parameter will not result in returning the average of vectors. This is an understandably confusing situation.